One of the main challenge that i felt that a btc user has to face is that they should be ready to take up any kind of risk while being a btc holder .The price of the btc market depends on the market trend and the btc holder has to be updated about the market trends or else they will end up in loss. Another thing which can affect a btc holder can be the unexpected ban that can come up in their nation if any government but ban on btc investment they will no longer be able to use btc in their nation and it can also affect the investor as they will be in huge loss and it is not everyone's piece of cake to afford btc these days.Apart from that it is the best investment decision one can do in this scenario.